Hi Richard, with JF 4238 (1933 Saloon) , the pulleys did turn the cable through 90 degrees. I use the standard cables as supplied by Ian Harris.
John
More brake cable questions
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Jpallis001
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Re: More brake cable questions
Thanks John. I'm sure the fitting and adjustment will be straight forward once the new cables from Ian Harris arrive and I stop fussing.
Thank goodness for Ian G. and the forum.
Thank goodness for Ian G. and the forum.
Re: More brake cable questions
Ian,
The new cables from Ian Harris have arrived and I've been down this afternoon to try them on the car. They measure just 42 inches but even allowing for the missing half inch they would still be way too short. I should have anticipated this from my measurement with the orange string on November 14 last which showed the neat length from the hole in the clevis to countershaft lever pin of 42 inches without any allowance for adjustment beyond the countershaft lever. Unlike the old ones the new cables are quite flexible and turn snugly around the two pulley wheels but they are still short by perhaps an inch and a half. If the nut is to just fit on the threaded rod through the countershaft lever with the new springs between the lever and the swage then I suspect that I will need even more length.
I seem to have exhausted all possibilities in understanding why this is so.
The brake cam lever lies forward, that is toward the front of the car, at 30 degrees from vertical with the cam faces horizontal and the shoes at their maximum contraction. I can't see how I can vary this without compromising the capacity of the lever to rotate the cam when the cable tightens.
I've slackened off the countershaft completely and even then the threaded rod won't reach the countershaft lever pin. In fact the countershaft needs to come back a fraction to allow the foot brake rod and the hand brake cable (7.8 inches) to reach their respective levers. I note in the March 1932 Service information No. SV/11 that the "working angle of the countershaft levers....should make an angle of approximately 60 degrees with their respective cables when in the "Off" position-that is, they should lean appreciably backward toward the rear of the car..." I assume that this refers to the foot and hand brake levers but in any event the angle will be the same.
I've checked again the position of the chassis pulley based on your advice of 15 November with the diagram and picture of the McEvoy bracket that you attached to that post. Based on your advice my bracket seems to be in the right position and indeed I can't see how I can move it backwards. It clearly needs two bolts to the chassis and the spacing of bolts further back are not the same. I still have some doubt on this particularly given the correspondence with John Pallis in December 2010 and his suggestion at that time that "there are two holes ...that would provide the 45 degree cable run" but he has joined this series recently with advice that on his 1933 Saloon the cables turn through 90 degrees and that he has fitted the standard cables as supplied by Ian Harris.
I'm assuming that the pulley on the king pin is in the right position and that the relationship of the front axle to the back plate and therefore the brake lever is fixed.
It even occurred to me that I was misreading the chassis number or that the number on the firewall plate did not match that on the dumb iron. I thought that perhaps the chassis was after 13542 (see the page from the Brivec spares catalogue and the specified E 220 cable at 44.25 inches) . No, both read SV 8159 and from that I must assume that 42.5 inches is the correct length. Neither is it likely to be a local adaptation by the body builder given that the car arrived as a rolling chassis....although the hydraulic shock absorbers are clearly not from the Cowley works.
The cables to the rear wheels seem original and have "morris" stamped onto the swage. They project an inch at least beyond the lever at the back plate although I do not have the guides to the chassis outrigger fitted which might take up some slack.
I could simply write back to Ian Harris and order some longer cables but this whole thing is starting to get to me. I'm clearly doing something wrong.
Can you think of anything else to try?
The new cables from Ian Harris have arrived and I've been down this afternoon to try them on the car. They measure just 42 inches but even allowing for the missing half inch they would still be way too short. I should have anticipated this from my measurement with the orange string on November 14 last which showed the neat length from the hole in the clevis to countershaft lever pin of 42 inches without any allowance for adjustment beyond the countershaft lever. Unlike the old ones the new cables are quite flexible and turn snugly around the two pulley wheels but they are still short by perhaps an inch and a half. If the nut is to just fit on the threaded rod through the countershaft lever with the new springs between the lever and the swage then I suspect that I will need even more length.
I seem to have exhausted all possibilities in understanding why this is so.
The brake cam lever lies forward, that is toward the front of the car, at 30 degrees from vertical with the cam faces horizontal and the shoes at their maximum contraction. I can't see how I can vary this without compromising the capacity of the lever to rotate the cam when the cable tightens.
I've slackened off the countershaft completely and even then the threaded rod won't reach the countershaft lever pin. In fact the countershaft needs to come back a fraction to allow the foot brake rod and the hand brake cable (7.8 inches) to reach their respective levers. I note in the March 1932 Service information No. SV/11 that the "working angle of the countershaft levers....should make an angle of approximately 60 degrees with their respective cables when in the "Off" position-that is, they should lean appreciably backward toward the rear of the car..." I assume that this refers to the foot and hand brake levers but in any event the angle will be the same.
I've checked again the position of the chassis pulley based on your advice of 15 November with the diagram and picture of the McEvoy bracket that you attached to that post. Based on your advice my bracket seems to be in the right position and indeed I can't see how I can move it backwards. It clearly needs two bolts to the chassis and the spacing of bolts further back are not the same. I still have some doubt on this particularly given the correspondence with John Pallis in December 2010 and his suggestion at that time that "there are two holes ...that would provide the 45 degree cable run" but he has joined this series recently with advice that on his 1933 Saloon the cables turn through 90 degrees and that he has fitted the standard cables as supplied by Ian Harris.
I'm assuming that the pulley on the king pin is in the right position and that the relationship of the front axle to the back plate and therefore the brake lever is fixed.
It even occurred to me that I was misreading the chassis number or that the number on the firewall plate did not match that on the dumb iron. I thought that perhaps the chassis was after 13542 (see the page from the Brivec spares catalogue and the specified E 220 cable at 44.25 inches) . No, both read SV 8159 and from that I must assume that 42.5 inches is the correct length. Neither is it likely to be a local adaptation by the body builder given that the car arrived as a rolling chassis....although the hydraulic shock absorbers are clearly not from the Cowley works.
The cables to the rear wheels seem original and have "morris" stamped onto the swage. They project an inch at least beyond the lever at the back plate although I do not have the guides to the chassis outrigger fitted which might take up some slack.
I could simply write back to Ian Harris and order some longer cables but this whole thing is starting to get to me. I'm clearly doing something wrong.
Can you think of anything else to try?
- Attachments
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- Another view of the bracket position.
- IMG_4780.JPG (625.04 KiB) Viewed 3744 times
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- The back plate and the kingpin pulley.
- IMG_4778.JPG (663.57 KiB) Viewed 3744 times
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- Just this little bit short.
- IMG_4774.JPG (523.41 KiB) Viewed 3744 times
Re: More brake cable questions
Richard,
This is very odd. I just checked my McEvoy chassis and can confirm that your chassis pulley brackets are correctly placed. Everything else in your latest photos looks correct, except I cannot see the cross-shaft - presumably it is the standard unit bracketed off the front chassis cross-member. The second thing I notice is that the cable itself is not wire rope. Wire rope should be smaller in diameter and braided. I'll see if I can take a photo of my originals tomorrow.
Other than that, it is beginning to look like the catalogue length is incorrect. It's late at night here in Seattle, so I will sleep on it and respond further in the morning.
Ian
This is very odd. I just checked my McEvoy chassis and can confirm that your chassis pulley brackets are correctly placed. Everything else in your latest photos looks correct, except I cannot see the cross-shaft - presumably it is the standard unit bracketed off the front chassis cross-member. The second thing I notice is that the cable itself is not wire rope. Wire rope should be smaller in diameter and braided. I'll see if I can take a photo of my originals tomorrow.
Other than that, it is beginning to look like the catalogue length is incorrect. It's late at night here in Seattle, so I will sleep on it and respond further in the morning.
Ian
Re: More brake cable questions
Ian,
Here is a picture of the cross-shaft (why am I calling it a countershaft?) bolted to the rear of the chassis cross member. I'm sorry about the non Enots nipple.
I assume that the shaft is correctly located as the bar/cable from the foot and hand brake fit to the levers as do the rear brake cables. If it is a catalogue error surely Ian Harris would have picked the mistake up by now or other SV owners would have had the same problem with his cables. I don't think it is the diameter or composition of Ian's cables, they are quite flexible.
If there is an error where is its origin? The Brivec Spares page that you posted to this topic on 31 October seems fairly clear although half way down the page under the heading "Brake Components (OHV & SV) are two items, two cables of different lengths.
Part No. E118/209 is described as "Brake Cable, Front<SWB and van, to Chassis 13541" and at the bottom of the page under "Overall lengths of brake cables" is further described as being 42.5" long.
Brivec Part No. E220/209 is similarly described as "Brake Cable, Front,SWB., Chassis Nos. 13542-33778 and at the page bottom as being 44.25" long.
Can you tell me what happened at 13542 to require a cable 1.75" longer? I assume a longer wheelbase but you will be much more precise given all the work you have done on the Genome and the changes introduced during production.
I have just now measured my wheelbase at 78" and a bit ..the SWB standard.
Here is a picture of the cross-shaft (why am I calling it a countershaft?) bolted to the rear of the chassis cross member. I'm sorry about the non Enots nipple.
I assume that the shaft is correctly located as the bar/cable from the foot and hand brake fit to the levers as do the rear brake cables. If it is a catalogue error surely Ian Harris would have picked the mistake up by now or other SV owners would have had the same problem with his cables. I don't think it is the diameter or composition of Ian's cables, they are quite flexible.
If there is an error where is its origin? The Brivec Spares page that you posted to this topic on 31 October seems fairly clear although half way down the page under the heading "Brake Components (OHV & SV) are two items, two cables of different lengths.
Part No. E118/209 is described as "Brake Cable, Front<SWB and van, to Chassis 13541" and at the bottom of the page under "Overall lengths of brake cables" is further described as being 42.5" long.
Brivec Part No. E220/209 is similarly described as "Brake Cable, Front,SWB., Chassis Nos. 13542-33778 and at the page bottom as being 44.25" long.
Can you tell me what happened at 13542 to require a cable 1.75" longer? I assume a longer wheelbase but you will be much more precise given all the work you have done on the Genome and the changes introduced during production.
I have just now measured my wheelbase at 78" and a bit ..the SWB standard.
- Attachments
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- The cross shaft bolted to the chassis cross member
- IMG_4784.JPG (621.76 KiB) Viewed 3741 times
Re: More brake cable questions
Richard,
Bit of head scratching going on here, but I might have got a clue from your first photo from yesterday.
There were two different chassis pulley brackets on Minors. I have been trawling through my images trying to find a photo of the early type, but without success so far. But it can be seen quite clearly in the 1931 season lubrication chart:
Note also that the pulley wheels were of a smaller diameter. This is the system that your chassis SV8159 should have, but it appears that it has the later bracket and pulleys.
The early type bracket shown in the drawing above (Morris part no. 5133) started on the OHC Minor at chassis M29528 and on the SV Minor from SV101, and ran through to SV chassis SV20300, i.e. the end of 1932 season production. The later, stronger type (Morris part no. 50396)ran from chassis SV20301 to SV33778 (i.e. the 1933 season).
So you have 1933 season brake brackets and pulleys on your 1931 season chassis.
According to Brivec, you should therefore have the later brake cables, which I believe switched from chassis SV20301, not SV13542 as stated in the Brivec catalogue. I looked up SV13542 in the Genome and it is in the middle of a batch of saloons of no particular note that were laid down in the middle of February 1932.
The reason for the upgrade was to introduce stronger brackets and larger diameter pulley wheels, thereby requiring longer cables.
The two types of bracket were attached with a different bolt arrangement. The early bracket simply had a pair of bolts (and therefore bolt holes in the chassis) that were side by side. It would be interesting to see if there is any evidence of these holes in your chassis. If not, then I would double check the chassis number on your chassis dumbiron, and whether the dumbiron is attached with its original rivets or has been bolted on from another chassis. (Chassis SV8159 left the works as a bare driving chassis, so presumably your tourer body is Australian-built?)
But for now, the question is - would cables that were 1.75" longer still be too short?
Bit of head scratching going on here, but I might have got a clue from your first photo from yesterday.
There were two different chassis pulley brackets on Minors. I have been trawling through my images trying to find a photo of the early type, but without success so far. But it can be seen quite clearly in the 1931 season lubrication chart:
Note also that the pulley wheels were of a smaller diameter. This is the system that your chassis SV8159 should have, but it appears that it has the later bracket and pulleys.
The early type bracket shown in the drawing above (Morris part no. 5133) started on the OHC Minor at chassis M29528 and on the SV Minor from SV101, and ran through to SV chassis SV20300, i.e. the end of 1932 season production. The later, stronger type (Morris part no. 50396)ran from chassis SV20301 to SV33778 (i.e. the 1933 season).
So you have 1933 season brake brackets and pulleys on your 1931 season chassis.
According to Brivec, you should therefore have the later brake cables, which I believe switched from chassis SV20301, not SV13542 as stated in the Brivec catalogue. I looked up SV13542 in the Genome and it is in the middle of a batch of saloons of no particular note that were laid down in the middle of February 1932.
The reason for the upgrade was to introduce stronger brackets and larger diameter pulley wheels, thereby requiring longer cables.
The two types of bracket were attached with a different bolt arrangement. The early bracket simply had a pair of bolts (and therefore bolt holes in the chassis) that were side by side. It would be interesting to see if there is any evidence of these holes in your chassis. If not, then I would double check the chassis number on your chassis dumbiron, and whether the dumbiron is attached with its original rivets or has been bolted on from another chassis. (Chassis SV8159 left the works as a bare driving chassis, so presumably your tourer body is Australian-built?)
But for now, the question is - would cables that were 1.75" longer still be too short?
Re: More brake cable questions
Ian,
Fascinating stuff. Tomorrow or Wednesday morning I will measure more accurately the distance from the clevis at the brake shoe lever to the back of the pin at the cross-shaft lever and make some judgement about the suitability of the 44.25" cables. The extra 1.75" does not seem much. Do you have any sense of how much threaded rod should project beyond the cross-shaft lever? I assume at least enough to allow the brass adjuster nut to be fully engaged. If you are also able to let me know what diameter the smaller pulleys are I will try to calculate how much less cable is used in turning one quarter of a circumference on each and whether that would amount to the present discrepancy.
I'm not too surprised at the possibility of 1933 brackets and pulleys on a 1931 chassis. Shipping from Cowley to an Australian dealership would have been time consuming by todays standards and the further delay in having a local body works complete the car may well have amounted to two years and an opportunity to introduce factory modifications. I suspect too that there were Australian specifications on some elements to deal with less refined road conditions than in Britain. Some may have been local initiatives but is it possible perhaps that some were recommended by Morris?
As you say however, the real question now is will the post SV 20301 cables be long enough.
Give me a day or two.
Fascinating stuff. Tomorrow or Wednesday morning I will measure more accurately the distance from the clevis at the brake shoe lever to the back of the pin at the cross-shaft lever and make some judgement about the suitability of the 44.25" cables. The extra 1.75" does not seem much. Do you have any sense of how much threaded rod should project beyond the cross-shaft lever? I assume at least enough to allow the brass adjuster nut to be fully engaged. If you are also able to let me know what diameter the smaller pulleys are I will try to calculate how much less cable is used in turning one quarter of a circumference on each and whether that would amount to the present discrepancy.
I'm not too surprised at the possibility of 1933 brackets and pulleys on a 1931 chassis. Shipping from Cowley to an Australian dealership would have been time consuming by todays standards and the further delay in having a local body works complete the car may well have amounted to two years and an opportunity to introduce factory modifications. I suspect too that there were Australian specifications on some elements to deal with less refined road conditions than in Britain. Some may have been local initiatives but is it possible perhaps that some were recommended by Morris?
As you say however, the real question now is will the post SV 20301 cables be long enough.
Give me a day or two.
Re: More brake cable questions
Just another unrelated observation. the bolts holding your backplates on are reversed - the heads should be inside and the nuts exposed. These bolts have special thin heads so as not to foul the brake shoes.
Re: More brake cable questions
I'll check this and the off side back plate nuts this afternoon. It doesn't seem to have been a problem.. or not one that I've noticed.
Re: More brake cable questions
Actually I think it is the back of the hubs that can foul these, but cannot be certain without looking.
Re: More brake cable questions
Thanks Ian.
Can you let me have the diameter of the early pulleys? I note that Ian Harris seems to offers only one size for all SV's 1931-34 although a bracket change at SV 13542 is acknowledged in Morris Part 50395/6
Can you let me have the diameter of the early pulleys? I note that Ian Harris seems to offers only one size for all SV's 1931-34 although a bracket change at SV 13542 is acknowledged in Morris Part 50395/6
Re: More brake cable questions
I don't have a diameter for the early SV pulleys. They were larger than the OHC pulleys and smaller than the later SV pulleys!
The OHC pulleys were 1.0" diameter with a 0.125" radius groove, so 0.75" inside radius for the cable.
(Technical drawings for the brake pulleys, pulley posts and shackles for the OHC chassis (to M29527), may be found in the Technical Drawings section of the main website Members' Area.)
The OHC pulleys were 1.0" diameter with a 0.125" radius groove, so 0.75" inside radius for the cable.
(Technical drawings for the brake pulleys, pulley posts and shackles for the OHC chassis (to M29527), may be found in the Technical Drawings section of the main website Members' Area.)